Mobile Ad-Hoc Networks (MANET) are well known and widely used for communication. A MANET is used, for example, by home security forces, the military, sensor networks, etc. Naturally, such ad-hoc networks are designed to support joining of multiple mobile devices to form a communication network, and to ensure a proper operation of the network when one or more of the “member” devices leave the network, for example, when exceeding the effective range with respect to one or more of other network devices. Some of said MANET networks are designed to allow sound communications between the member devices.
US 2008/0268855 discusses dynamic allocation of bandwidth by a “master” device to “router stations” (routers), following receipt from said routers of bandwidth requirement information, respectively.
While ad-hoc networks of the prior art typically include adaptations to structural variations in the network due to joining, separation, or changes in locations of the each specific mobile device within the network, still those structural variations in said prior art networks occur relatively slow, typically in the range of one variation every several minutes or more. Furthermore, the MANET systems of the prior art typically support a half-duplex sound communication (i.e., “walkie talkie” type of communication), not a full duplex, or conference type of sound communication in which two or more users (for example, four) can conduct a simultaneous discussion. It should be noted that achieving such type of communications in a seamless manner requires resolving significant complications, in view of propagation delays of the sound signals to all the network devices, and in view of processing times within the devices.
For example, the ad-hoc sound communication networks of the prior art are not suitable for conducting full duplex, conference type of discussion by a plurality of motorcyclists or mobile devices users. More specifically, in the motorcycle environment, there is a necessity for an ad-hoc, full duplex sound communication network which enables a plurality of motorcyclists (for example up to 10 motorcyclists) to participate in a simultaneous “conference call”, in which any of the riders can talk and randomly upper limit of 4 of them can be heard at all times by all of the other motorcyclists who participate in the conference call, or join the conference call at will. The fact that motorcycles move in high speeds such as 150 kilometers per hour or more and randomly change their respective positions in the group results in frequent network structural variations, i.e., variations in a rate which cannot be handled by prior art ad-hoc sound networks. Moreover, these frequent variations in the network structure add still another significant difficulty to said need for supporting full-duplex, even conference type of sound communication between the various devices.
Still another necessity which may exist, for example, in the motorcyclist or mobile devices environment is to allow additional participants that are external of the MANET system to join the conference call. For example, upon establishment of a MANET conference call between 4 motorcyclists, a fifth participant which is external of the MANET, but having a telephone mobile communication (or any other communication) with one of the MANET participants may wish to participate in the conference discussion. Such an option has never been provided by the prior art. This necessity may also exist for professional users e.g. enterprise and public safety users that move in areas where communication infrastructure coverage is partial or may be damaged, requiring continuation of the mobile communication, using off-network MANET. Such group of users is also very dynamic and requires full duplex conference call.
It is therefore an object of the present invention to provide an ad-hoc sound communication system which can handle significant and frequent structural variations that may occur in rates of seconds, while still providing a full duplex, conference type of communication between several member devices.
It is another object of the present invention to optionally include a hopping type of sound communication between devices of said ad-hoc network, and to handle structural variations in said hopping structure.
It is still another object of the present invention to provide an easy and simple procedure for configuring the devices that join the network.
It is still another object of the present invention to account for a loss of communication with ad-hoc key devices, such as “leader”, relays or “synchronize” respectively, while enabling prompt recovery and proper operation of the network even following said loss of communication with said key devices.
It is still another object of the present invention to easily and dynamically enable modifications in the structure of the network.
It is still another object of the invention to enable connectivity between two or more types of networks, one of them is a MANET network and the other is, for example, a packet switching (LAN/WAN) network or a circuit switching (cellular) network, by using of one or more of the MANET participant devices to establish said multi-network connectivity.
It is still an object of the present invention to provide said ad-hoc sound or data communication system which is suitable, among others, for motorcyclists use.
Other objects and advantages of the present invention will become apparent as the description proceeds.